Diaphragm for telephonic apparatus



23 19 Aug 7 G. LAKHOVSKY DIAPHRAGM FOR TELEPHONIC APPARATUS Filed June 5, 1924 IN YEN OR (1207 yes I ak/ZOUS/{Q B y A TTOR/VE rs Patented, Aug. 23, 1927.

UNITED STATES 1,640,33t PATIENT. OFFICE.

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Application fledIune'5', 1924,'er1a1No. 718,127,-a i1d1n-France June 14, 1923.

The experiments of the inventor have shown that, in apparatus ,forvtransmittmg sounds, either emitting or receiving apparatus, e. g., receivers or transmitters, it is advantageous to arrange the movable plates or diaphragms in such a manner that they'- impart vibrations to the molecules of air in contact with them, but do notv1brate themselves. Under these conditions ,it 1s possible to avoid the distortion or destruc metallic plates, with interposition between them of a dam ing material.

This materia can be a last1c, or VlSCOllS rubber.

Moreover, the plates the assemblage of which forms the subject-matter or the invention are provided with ribs th1sg1v ng ing of the vibrations is concerned.

Preferably thesaid plates are provided with s milar ribs so as to exactly fit in each other.

The late thus constituted is mounted in the casing of the apparatus-b means of dam ing rings, ade of rubber r instance,

or o a singlering provided with anannular recess in which fits the edge of the plate.

This. invention is illustrated, but by way of example only, in the accompanying drawin in which: I

%igure 1 is a plan view of the diaphragm;

and Figure 2'is a section on line B-f-B of by means of twoor more 'diaphragms, or-

, substance,,for instance, oi or a solution of them special properties as far as the damp Referring to the drawing a and. a repre- 4 the plates a and a isiinterposed a layer of The whole is set or fitted in a rubber ring '11 provided with an inner, annular slot or recess j wherein exactly fits the edge of the plate constituted by the whole of the above elements.

This ring might be replaced by two rings madeof rubber or other non-sonorous material (for instance, lead, ebonite, etc.) arranged on. either side of the edge of the vibrating plate.

Experience shows that the plates and the system thus constituted/give very good results concerning the oureness and clearness of the sounds and absence of distortion of the joints.

The diaphragm when mounted in a casing will, owing to the ring 2', .have no contact.

with the casing, so that it cannot transmit vibrations to the same and rev'ersely.

The new vibrating plates or diaphragms are applicable to any apparatus for transmitting sounds, either emitting or receiving apparatus.

I The above arrangement is given by way of example only; the form, materialsand dimensions .can be varied without departing thereby from the principle ofthe invention.

LA diaphragm for sound sending and receiving apparatus formed of two thin discs provided with. registering grooves, and a layer of viscous material interposed between the discs whereby, the diaphragm-is absolutely without tone.

2. A diaphragm for sending vand receiving apparatus formed of two thin metal discs provided with registering grooves, a layer pf: viscousmaterial interposed between the discs, whereby the diaphragm is absolutely without tone,-anda rubber ring, on'the pe ripheries of the discs and retaining the viscons material between the said discs,

3. A diaphragm consisting of two thin metal discs, each provided'with' two concentric grooves, and radial grooves connect .ing the concentric grooves, the grooves of the discs registering, alayer of viscous material between the discs, and a rubber ring on theperipheries of said discs.

' The foregoing specification of my improvements in diaphragnis for tele honic apparatus, signed by nie this 21st ay of May, 1924.

GEORGES LAKHOVSKY. 

